Those exterior inline filters are next to useless. Some have a very high micron rating and don't filter much sediment. They can plug up and/or lose their efficacy quickly. At least use one with KDF in it which is their to reduce the growth of bacteria and pathogens ON the filter (not flowing out of it). In high ambient temperatures with the filter getting little or no use, bacteria can thrive. It's not a good idea to use an exterior filter with carbon in it to remove chlorine because bacteria can potentially thrive inside your RV water's system. If you want to remove chlorine, use a point-of-use filter.
It's possible that there is bacterial growth on the filter. Does the water smell just as bad straight out of the CG faucet? What does it look like in a glass? Being cloudy is not necessarily a bad thing and can just be an aesthetic turbidity issue. If it's a CG that you frequent, you could always discuss it with the local water supply authority unless it's on a private well. I did that earlier this year at our regular CG and the local authority ended up flushing the line near the CG.
In warmer weather, it helps to store your filter(s) in your fridge between camping trips to minimize bacterial growth.
We have a 4-stage filter setup under our kitchen sink using 10" whole house cartridges. The 3rd filter is a Doulton ceramic Ultracarb and the last filter is an ultrafiltration Crystal Quest cartridge of around 0.2 microns (which is very low).
There are many better filters that can be used. This is a vendor that has some good info. on filters along with filters and other related items for RV use.
RVwaterfilterstore.com There is general filter info. here (scroll towards the bottom)
waterfilters.net